Reservoir heterogeneity is a main factor influencing efficient oil reservoir development. For improving a water drive development effect of an oil reservoir in middle and later periods, it is necessary to regulate the heterogeneity of a stratum. In various process measures, injecting a polymer, or a polymer-based binary/ternary composite flooding system, gel, a polymer microsphere and the like is important technical means for regulating the oil reservoir. However, the technical measures have some problems in an oil reservoir mine implementation process. Factors such as shearing of a ground surface injection device, shearing of stratum seepage, physical and chemical properties (temperature, mineralization degree, pH value and the like) of the stratum and stratum water dilution result in relatively high loss in viscosity of polymer-based binary/ternary composite flooding system, gel, a polymer microsphere and the like, weakening of a fluidity control capability, relatively fast injection pressure reduction particularly in a subsequent water drive stage and difficulties in achieving a long-term effective regulation effect. For a polymer-based gel system, under the influence of shearing and dilution actions, an effective concentration of the polymer injected into a gel forming solution of the stratum is decreased, and the polymer is structurally damaged, so that gel forming time of the gel is indeterminate, a gel forming intensity is reduced, and the regulation effect is reduced; and particularly for a low-permeability oil reservoir, a shearing effect is more obvious. The polymer microsphere is prepared from monomer acrylamide (AM), and is poor in environment friendliness, and a preparation process is relatively complex and high in cost.
In view of the problems of above regulating agent and in combination of the characteristic of controllability of an oilfield, a method for preparing an environment-friendly multiscale zirconium dispersed particle gel blocking agent is disclosed in CN102936490A. According to the method, a certain crosslinking technology and dispersion technology are adopted, and an aqueous dispersion solution distributed with different particle sizes is prepared from bulk gel formed on the ground surface after a mechanical shearing action. The multiscale dispersed particle gel particle has high viscoelasticity, in a stratum, it may change shape according to size and shape changes of an aperture, and then migrate to a deep part along, it also may avoid the influence of ground surface shearing, shearing of subsurface seepage and physical and chemical properties, which are however suffered by a polymer type regulation system, so the multiscale dispersed particle gel particle can meet a large-scale industrial production requirement, and is environment-friendly. Nanoscale, micron-scale and millimeter-scale zirconium dispersed particle gel obtained by the method can enter the deep part of the stratum through their own particle sizes and be gathered and expanded at the deep part of the stratum, can effectively regulate a water injection profile of the stratum, and has a relatively high fluidity control capability. However, the formed zirconium bulk gel has poor viscoelasticity,
An integrated dispersed particle gel continuous online production and injection method is disclosed in CN102996106B. The method includes two parts, i.e., dispersed particle gel production and injection, and industrial workshop production of dispersed particle gel and rapid well field injection may be implemented. Based on the method, a multiscale dispersed particle gel production process may be regulated to implement integration of production and injection of the dispersed particle gel. However, the process of the present invention mainly involves industrial workshop production of the dispersed particle gel, and for a complex environment such as a tidal flat, a hill and an offshore work platform, long-distance transportation, high packaging cost and the like greatly increase operation cost in deep profile control (profile control) of the dispersed particle gel and limit large-scale application of the dispersed particle gel to a complex oil reservoir. In addition, chemical reaction of the bulk gel involved in the patent is only performed at room temperature, it is difficult to implement reaction of a medium/high-temperature bulk gel system, and a using requirement of a medium/high-temperature high-salt oil reservoir may not be met.